The transplant was a five-minute procedure in which the donor cells from Robin's sister, Sally-Ann, were injected into Robin's system through a syringe.

"Nobody can believe it," Dr. Gail Roboz, the New York-Presbyterian Hospital/Weill Cornell Medical Center oncologist who is treating Robin, said Friday on "GMA" of the short procedure.

"People have in their mind all kinds of images of what can happen in a transplant but it's still an incredibly powerful moment," she said. "Inside of that syringe are millions and millions of stem cells that are now circulating around and trying to find their home and start growing which is what we're going to be looking for over the next couple of weeks."

As she underwent the transplant Robin was surrounded by her siblings and other loved ones, including "World News" anchor Diane Sawyer and "GMA"'s weather anchor, Sam Champion.

"It was an emotional, scary and yet exhilarating moment, one that I'll never forget," Champion said.

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Robin faced the procedure with grace, strength and humor. For 10 days prior to the transplant, she endured rigorous chemotherapy treatments to prepare her system to accept her sister's cells.

Prior to the procedure, the Rev. A.R. Bernard prayed. Then, slowly and steadily, Dr. Sergio Giralt injected the millions of donor stem cells. After the procedure, Robin and her family and friends broke out in one of her favorite songs, "Ain't No Mountain High Enough."

"I will now wait and anxiously watch and see what happens," Robin said after the procedure. "In the next seven to 10 days my counts will continue to go up and we'll be on to phase three, which will be get out of here. Get out of here. Go home. It's a journey."

So what's next?

"I got a good email this morning," Roboz said. "This morning she [Robin] sounds energized and she wants to be out of bed and the end of the email was "I want to go home" with an exclamation point."

Robin, according to Roboz, will lack energy in the next few days. She may have persistent indigestion and heartburn, and won't have much of an appetite. She will have chills, and may have a fever.

"We have to roll with the punches over the next few days because, don't forget, her systems are down and Sally-Ann's aren't up yet so we're in that in between zone of watching very carefully," she said. "We are wanting every day to be a good day but we are ready for some bumps in the road."

Doctors will treat Robin with intravenous fluids, electrolyte replacement and anti-viral, anti-bacterial and anti-fungal medications, Roboz said. Though she'll be monitored daily, doctors won't expect to see significant signs of recovery for about 10 days. They will closely watch her for signs of infection.

Since her immune system was destroyed to make way for the new cells, she would be unable resist infection in her own.

"We actually check blood sometimes several times a day," Roboz said. "You can start seeing normal blood cells recover and usually what I tell people is when you get three days in a row of the white blood cells coming up, then you're starting to get excited that the graf is taking hold. The stem cells are talking hold and maybe we're going to start getting to he finish line and getting out of the hospital."

In two weeks or so, Robin should begin to feel better. Once the transplanted cells start to do their job, there is generally significant improvement in how patients feel, Roboz said. The primary goal of the transplant is to get Robin's system to correctly produce white blood cells and platelets.